From: Numan Siddique <num...@ovn.org> When ovn-controller injects IPv6 NS packet to learn the mac, in some setups it is observed that the packet is dropped by ovs-vswitchd. We see below logs
2019-11-18T10:42:17.973Z|00001|ofproto_dpif_upcall(handler6)|INFO|received packet on unassociated datapath port 4294967295 2019-11-18T10:42:18.221Z|00001|ofproto_dpif_upcall(revalidator8)|WARN|Failed to acquire udpif_key corresponding to unexpected flow (Invalid argument): ufid:9ba1081f-a692-4c1c-a79b-d1cf04175f7d Upon further debugging I noticed that, xlate_lookup() fails when there is upcall from kernel datapath because of ct related actions. When ovn-controller injects the packet it sets inport=CONTROLLER. This patch addresses this issue by avoiding the IPv6 NS packets to be sent to conntrack in the router egress pipeline. This should be ideally fixed in ovs-vswitchd. Reported-by: Russell Bryant <russ...@ovn.org> Signed-off-by: Numan Siddique <num...@ovn.org> --- northd/ovn-northd.8.xml | 9 +++++++++ northd/ovn-northd.c | 5 +++++ 2 files changed, 14 insertions(+) diff --git a/northd/ovn-northd.8.xml b/northd/ovn-northd.8.xml index 78b1e84ad..956a10362 100644 --- a/northd/ovn-northd.8.xml +++ b/northd/ovn-northd.8.xml @@ -2826,6 +2826,15 @@ nd_ns { changed based on the configuration in the OVN Northbound database. </p> + <ul> + <li> + A priority-120 flow to advance the IPv6 Neighbor solicitation packet + to next table to skip SNAT. In the case where ovn-controller injects + an IPv6 Neighbor Solicitation packet (for <code>nd_ns</code> action) + we don't want the packet to go throught conntrack. + </li> + </ul> + <p>Egress Table 1: SNAT on Gateway Routers</p> <ul> diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c index 41e97f841..ccccd9651 100644 --- a/northd/ovn-northd.c +++ b/northd/ovn-northd.c @@ -7976,6 +7976,11 @@ build_lrouter_flows(struct hmap *datapaths, struct hmap *ports, ovn_lflow_add(lflows, od, S_ROUTER_OUT_UNDNAT, 0, "1", "next;"); ovn_lflow_add(lflows, od, S_ROUTER_OUT_EGR_LOOP, 0, "1", "next;"); + /* Send the IPv6 NS packets to next table. When ovn-controller + * generates IPv6 NS (for the action - nd_ns{}), the injected + * packet would go through conntrack - which is not required. */ + ovn_lflow_add(lflows, od, S_ROUTER_OUT_SNAT, 120, "nd_ns", "next;"); + /* NAT rules are only valid on Gateway routers and routers with * l3dgw_port (router has a port with "redirect-chassis" * specified). */ -- 2.23.0 _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev